Improvement in the art of forming grooves in sewing-machine needles



G. H. DIMD'ND.

I Forming Grooves in ASewing-Machine Needles,

Patented June 23,1874.

UNITED STATES PATENT OFFICE.,

GEORGE Il. DIMOND, OF BRIDGEPORT, CONNECTICUT.'

IMPROVEMENT IN THE ART OF FORMING GROOVES IN SEWING-MACHINE NEEDLES.

Specification forming part of Letters Patent No. 152,346, dated June 23, 1874; application tiled May 29, 1874.

To all 'whom it may concern:

Be it known that I, GEORGE H. DIMOND, of Bridgeport, in the county of Fairfield and State of Connecticut, have invented a new and useful Improvement in the Art of Forming the Grooves of Sewing-Machine Needles, of which the following is a specification:

My invention consists in forming the groove in the needle by a succession of blows from a punch as the needle-blank traverses a die. The subject-nmtter claimedis hereinafter specified.

The accompanying drawings show mechanism of the construction best adapted to carry out my invention now known to me. Obviously, however, the details of the mechanism may be varied by the substitution of wellknown mechanical equivalents without departing from the principle of my invention.

Figure l is a plan; Fig. 2, a vertical central longitudinal section on the line ac ai of Fig. l; Fig. 3, a view, in perspective, of the die-bloek or anvil; Fig. 4, a similar view of the groove-forming plate; and Fig. 5, a vertical central section through the clamp on the line y y of Fig. l.

The mechanism is contained within a stout frame, A. A feed-screw, B, actuated by any suitable well-known means, tra-verses a needlecarrier, C, in which the needle to be grooved is held by a clamp, D, consisting of two parallel plates, d d1, arranged one above the other, and having a grooverin them for the reception of the shank of the needle. These plates have a short vertical movement on guides d2, for a purpose hereinafter explained, and are held together by a clamp-screw, d3. The carria-ge C moves horizontally on its bed, and carries a cam, c, of the contour shown in Fig. 2. A dieblock or anvil, E, movable vertically in suitable guides, but held snugly laterally, rests upon and is reeiproeated by this cam. The die-block has an eye, c, for the passage of the needle, and a slot, f, in which a punch, F, works. This punch may be actuated in any of the numerous wellknown ways, which are so well understood as to require no illustration here. A plate, G, having a grooving-die, g, therein, is secured upon the frame by locking-buttons g', which enter grooves in its sides, thus holding it securely, but allowing it easily to be removed or replaced.

In operation, a needle-blank is secured in the clamp in proper position, and fed beneath the punch, which reciprocates rapidly and forms the groove by a succession of blows. Any desired contour of the bottom of the groove may be secured by varying the contour of the cam c. In the drawing the cam is shown as rising' from its front edge toward its center; consequently, as the carrier O advances, the die-bloekE is raised and the groove in the needle is gradually deepened from the point backward. Uien the traverse of the carrier is reversed the top of the needle bears against the top of the grooving-die g, and the edges of the groove are curved slightly inward, so as partially to overlap the body of the groove in order that the thread may be more perfectly protected. This overlapping takes place on the deeper portions of the groove only, as the sinking of the die-block E as the cam slides from under it relieves the pressure of the needle on the groovingdie g. The clamp-screw d, it will be observed, is on one side of the needle,and the clamp itself conforms freely to the vertical movements of the needle in the die-block.

I claim as my invention- The improvement in the art of forming the grooves in sewing-machine needles, substantially as hereinbefore set forth, by subjeetin g the needle to a succession of rapid blows from a punch as it traverses a die.

In testimony whereof I have hereunto subscribed my name.

GEO, E. mMoND.I

Witnesses GEO. TreKNoR,

CHARLES DIMOND. 

